Watertube boiler



Patented Aug. 8, 1944 UNITED STATES PATENT OFFICE 2,355,279

WATERTUBEoILER4 John B. Detwiler, Mimico, Ontario, Canada Application December 2, 1941, Serial No. 421,331 5 Claims.k v(Cl. LZ2- 169) This invention relates to improvements in boilers particularly adapted for steam or hot Water heating and the principal objects are to ensure the maximum transfer of heat units from the fuel to the water in the -minimum of time.

' A further and important object is to devisev a form of `boiler giving the maximum efficiency 'which may be manufactured at reasonable cost and will lmaintain its effective use for a maximum period.

The principal feature of the invention consists in the novel construction and arrangement of Aan auxiliary heating element within the combustion chamber of the furnace, such heating element comprising an arrangement of annular tubes having transverse circulating tubes interconnected to circulate water from the jacket of the combustion chamber progressively through the annular tubes to be super-heated and to be ultimately discharged into the upper portion of the combustion chamber jacket.`

In the accompanying drawing,

Figure 1 is a longitudinal vertical sectional view through a boiler constructed in accordance with this invention.

Figure 2 is a horizontal sectional view taken through the line 2 2 of Figure 1.

Figure 3 is a part plan and part horizontal section taken on the line 3-3 of Figure 1. Figure 4 is a vertical transverse section through a boiler taken on the line 4 4 of Figure 2.

Figure 5 is a Vertical elevation in part; section ofthe superheater showing the connection of the rings with the inlet and showing the vertical connections between the several rings.

In the manufacture of steam and water-heating boilers numeroustypes of superheating coils have been proposed to be placed within the main combustion chamber and the present invention has been devised with the particular purpose of achieving a much more rapid absorption of heat Aand circulation of the heat transfer medium than has hitherto been obtainable, with a consequent increase in elliciency and the present construction is of such a nature as to readily accommodate the variance in expansion and contraction.

In the construction herein shown the outer and inner shells I and 2 are spaced apart and supported upon a base 3 and are provided with the usual fire-door and smoke-nue orices 4 and 5 respectively and a flue-cleaning orice 6.

This shell structure may be of round, oval or rectangular construction and arranged within the interior of the combustion chamber enclosed by the inner shell 2 is my improved form of superheater. This superheater consists of a plurality of endless annular tubes l, 8, 9 and I Il which are spaced vertically apart, and each of these annular tubes is provided with an arrangement of a plurality of transverse cross tubes II, I2, I3 and I4, the ends of which open into the interior of the annular tubes and are welded securely thereto.

The central pair of tubes II and I2 of the lower ring 'I are formed with openings Yin the bottom side centrally of their length and a large tubular member I5, which is preferably of oval shape and of a sufficient diameter to span the pair of tubes, is tted against the contour of the undersurface of these tubes surrounding the openings cut therein and is welded securely thereto.

A cross piece I6 is welded between the adjacent parallel sides of the tubes II and |2-Yand to the top edge of the tube said inlet tube. The tube I5 elbow I1 and 'a horizontal portion I8 extends through the inner shell 2 so that water from the water jacket surrounding the combustion chamber may flow into the tube I5 and flowing upwardly it is directed into the two transverse tubes II and I2.

Water ilowing in the manner described is directed in the annular tube 'l at opposite sides, consequently the direction of ow in the circular tube 'I will be as indicated by arrows in Figure 2 in an outward direction, causing it to flow around the remainder of the perimeter of the tube 'I and to pass partly through the tubes I3 and I4..

The annular tube 8 spaced above the tube 'I is provided with transverse tubes similar to the tubes II, I2, I3`and I4, and the tubes I3 and I4 and also the outward parts of the tubes. I and 8 are connected by vertical tubes I9 and 20 so that the water flowing in through the tube I5 and carried to the ring tube 'I by means of the tubes II and I2` is picked up from the tubes I3 and I4 as well as from the outer portion of the ring tube and carried to the ring 8 thereabove.

'I'he circulation in the ring 8 is reversed to that in the ring 1, and water flowing into the tubes I3 and I 4 and the ends of the ring tubes Hows inwardly into the pair of middle tubes and it is picked up from the centre of these middle tubes by a large tubular ferrule 20 which is provided with an' connects with openings in the top of the cenl tral tubes and carries the water upwardly into openings in the bottom of the central tubes of I5 to seal the top of andrings.` i r 2. In a boiler,.:the `combination `witha water 2.1;' L Q f 2,355,275

the next annular tube 9, the connections being cross tubes and the outer portion of the rings and these vertical tubes conduct the water to the top ring I0 through the outer member, and the water thus fed to the top ring is circulated to the ends .of the central cross tubes 23 and 24 and it flows from openings in the centre of the top side of these cross tubes and is conducted by a tubular connection 25, similar to I5, in an 11p-.

Ward direction and discharged-into the space between the crown sheets of the innerjand oute'r jackets of the boiler. Y Y

The delivery of a superheatedwater or steam at the top of the crown of the combustionchamberprovides a supply of hot uid in direct alignment with the discharge opening 26 from the boilerand whilethis will mingle to a certain extent with',l the heated Water or steamnowing up from the side portions of .the 4boiler shell, it neverthelessprovides a :direct supply ofsuperheated fluid.

YThe structure as herein described is4 preferably formed of steel or copper tubingvvith the i central tubesofthe Vtop 'ring with the water joints Lin the several tubes allv welded together but it'will be understood ythat astructure similar to that `.shown maybe made yby providing `cast sections and by the use of nipples and couplings a structure similarto ,thatshown may befabricated, andsuch a structure Vwill supplyy the essential features of a superheater which will, be-

cause of being arranged directly in the path orf/ the gases of combustOn, absorb a maximum quantity of heat and transfer it directly to the L,

small streams of fluid flowing through the tu-bular structure, and such circulation Vwill pass the fluid through a maximum length of tubular ducts submitted directly to the applied heat.

AWhat I claim as myinvention is: j Y

' yljnav boiler, lthe combination with a water jacketed combustion chamber, of a plurality .of horizontal annular tubular members spaced apart within `said combustion chamber reach having` centrally arranged transverse tubes and tom central tubes with the Water jacket, Ytubular means connecting the central openings of a vertically adjacent pair of central tubes arranged between said top and bottom members, and vertical tubes connecting the outer transverse tubes jacketed combustion chamber, of ,a pluralityof annular tubes vertically spaced apart within said combustion chamber and arranged in pairs and each having centrally arranged transverse tubes and transverse tubes arranged at either side of the central tubes, a tubular duct leading from the said water jacket to the central tubes of the lower annular tube, vertical tubes connecting the outer tubes of the lower and upper pairs of annular tubes, a central duct connecting the central tubes of theupper Vof the lower pairof annular tubes and the central ducts of the lower of the upper pair of annular tubes, and a tubular duct leading from the central cross tubes of the upper annular tube.

"3, lIn a boiler, the combination with a water jacketed .combustion chamber, of a plurality of tubular rings horizontally arranged Vand spaced apart, each 'of said rings having a plurality of K openings in the inner perimeter, transverse tubes arranged parallelly within each of said rings and having their ends lfitted and welded tothe -innerfwall of said ring around said openings, up-

right tubes connecting the outer rings and outer cross tubes in pairs, means connecting the adjacent central tubes Vof the adjacent pairs of rings, means'I connecting the-central tubes of the bottom 'ring'with` the water-jacket of the boiler,

said central tube connections being adapted to direct the flow-of water in dividedfstreams in opposite directions, and means connecting the vcombustion chamber and with the upper and llower tubular members'. Y

5. 4-In a boiler, the combination with a water jacketed combustion chamber, of a plurality of annular tubular members vertically. spaced apart Within said combustionv chamber and each having a plurality of cross tubes the ends of which open .into saidannular tubes, short vertical tubular connections between cross tubes of the lowest annular tube and cross tubes of the next-adjacentk annular tube thereabove, short vertical tubes connecting' cross Ytubes of the latter Vannula'r tubemwiththe succeeding annular tube immediately thereabove, the vertical tubes between the succeedingltubes being arranged in staggered relation, a tubular. duct leading from said water jacketr to the lowest tubular member, anda tubular duct leading from .the centre ofthe top 1 JOHNB. DE'I'WILER, 

